#include <stdio.h>
int main()
{	       	   	
    float x, y;

    printf("Please input x:\n");
    scanf("%f", &x);

    if (x < 0)            //1
    {	       	   	
        y = 2 * x + 1;          //1
    }
    else if (x > 0 )          //1
    {	       	   	
        y = 1 / x;               //1
    }
    else  //1
    {	       	   	
        y = x;              //1
    }

    printf("y=%f", y);     //1

    return 0;
}	 